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arXiv · 1511.05051

Exposing local symmetries in distorted driven lattices via time-averaged invariants

Thomas Wulf·Christian V. Morfonios·Fotis K. Diakonos·Peter Schmelcher
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Abstract

Time-averaged two-point currents are derived and shown to be spatially invariant within domains of local translation or inversion symmetry for arbitrary time-periodic quantum systems in one dimension. These currents are shown to provide a valuable tool for detecting deformations of a spatial symmetry in static and driven lattices. In the static case the invariance of the two-point currents is related to the presence of time-reversal invariance and/or probability current conservation. The obtained insights into the wavefunctions are further exploited for a symmetry-based convergence check which is applicable for globally broken but locally retained potential symmetries.

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Thomas Wulf, Christian V. Morfonios, Fotis K. Diakonos, Peter Schmelcher. 2016-02-19. Exposing local symmetries in distorted driven lattices via time-averaged invariants. https://doi.org/10.1103/physreve.93.052215

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